Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: Research Article Scalable and Media Aware Adaptive Video Streaming over Wireless Networks | Hindawi Publishing Corporation EURASIP Journal on Advances in Signal Processing Volume 2008 Article ID 218046 11 pages doi 2008 218046 Research Article Scalable and Media Aware Adaptive Video Streaming over Wireless Networks Nicolas Tizon1 2 and Beatrice Pesquet-Popescu1 1 Signal and Image processing Department TELECOM ParisTech 46 Rue Barrault 75634 Paris France 2R D Department Sociéte Francaise du Radiotelephone SFR 1 Place Carpeaux Tour Sequoia 92915 La Defense France Correspondence should be addressed to Beatrice Pesquet-Popescu Received 29 September 2007 Accepted 6 May 2008 Recommended by David Bull This paper proposes an advanced video streaming system based on scalable video coding in order to optimize resource utilization in wireless networks with retransmission mechanisms at radio protocol level. The key component of this system is a packet scheduling algorithm which operates on the different substreams of a main scalable video stream and which is implemented in a so-called media aware network element. The concerned type of transport channel is a dedicated channel subject to parameters bitrate loss rate variations on the long run. Moreover we propose a combined scalability approach in which common temporal and SNR scalability features can be used jointly with a partitioning of the image into regions of interest. Simulation results show that our approach provides substantial quality gain compared to classical packet transmission methods and they demonstrate how ROI coding combined with SNR scalability allows to improve again the visual quality. Copyright 2008 N. Tizon and B. Pesquet-Popescu. This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use distribution and reproduction in any medium provided the original work is properly cited. 1. INTRODUCTION Streaming video applications are involved in an increasing number of communication services. The .
